// 求一组数据的标准差

package main

import (
	"fmt"
//	"math"
)

func sum(numbers []float64) (total float64) {
	for _, x := range numbers {
		total += x
	}

	return total
}

func main() {
	numbers := []float64{1, 3, 4.5, 2, 1}
	fmt.Println(sum(numbers))
}
